Bug 132377

Summary: REGRESSION (r168046): [New Multicolumn] Painting order is wrong for columns and fixed positioned elements
Product: WebKit Reporter: Dave Hyatt <hyatt>
Component: Layout and RenderingAssignee: Dave Hyatt <hyatt>
Status: RESOLVED FIXED    
Severity: Normal CC: commit-queue, eric.carlson, esprehn+autocc, glenn, jer.noble, kondapallykalyan, philipj, sergio, simon.fraser, WebkitBugTracker
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Test case
none
Patch simon.fraser: review+

Description Dave Hyatt 2014-04-29 22:46:06 PDT 
Check out fast/events/offsetX-offsetY.html and move the column block over the fixed positioned element. Everything paints behind the fixed positioned element when the foreground text should paint on top of it.
Comment 1 Dave Hyatt 2014-04-29 22:46:22 PDT 
I don't think this blocks turning new multicolumn on, but it *will* be important to fix.
Comment 2 Dave Hyatt 2014-04-30 15:20:48 PDT 
Created attachment 230530 [details]
Test case

Test case. Note that repainting (e.g., selection) is broken too.
Comment 3 Dave Hyatt 2014-04-30 18:00:20 PDT 
This is fixed by changing the layer for the flow thread to be normal flow only but still make it be self-painting.
Comment 4 Dave Hyatt 2014-04-30 18:18:02 PDT 
Created attachment 230551 [details]
Patch
Comment 5 Simon Fraser (smfr) 2014-04-30 18:20:24 PDT 
Comment on attachment 230551 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=230551&action=review

> Source/WebCore/rendering/RenderLayer.cpp:6406
> +        || renderer().isInFlowRenderFlowThread())

Can you indent this line or unwrap it.
Comment 6 Dave Hyatt 2014-04-30 19:13:30 PDT 
Fixed in r168076.
Comment 7 Alexey Proskuryakov 2014-05-01 00:05:53 PDT 
This change broke fast/multicol/fixed-stack.html:

http://build.webkit.org/results/Apple%20Mavericks%20Release%20WK2%20(Tests)/r168087%20(5354)/fast/multicol/fixed-stack-diffs.html
Comment 8 Alexey Proskuryakov 2014-05-01 00:06:48 PDT 
More precisely, this new test fails on all WK2 testers.